x²-8x-9≤0怎么解,过程.O(∩_∩)O谢谢
问题描述:
x²-8x-9≤0怎么解,过程.O(∩_∩)O谢谢
答
x²-8x-9≤0
(x-9)(x+1)≤0
-1≤x≤9
x²-8x-9≤0怎么解,过程.O(∩_∩)O谢谢
x²-8x-9≤0
(x-9)(x+1)≤0
-1≤x≤9